/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.iotdb.confignode.persistence.partition.maintainer;

import org.apache.iotdb.common.rpc.thrift.TDataNodeLocation;
import org.apache.iotdb.tsfile.utils.ReadWriteIOUtils;
import org.apache.thrift.TException;
import org.apache.thrift.protocol.TProtocol;

import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import java.util.Objects;

public abstract class RegionMaintainTask {

    protected final RegionMaintainType type;
    protected TDataNodeLocation targetDataNode;

    protected RegionMaintainTask(RegionMaintainType type) {
        this.type = type;
    }

    public RegionMaintainType getType() {
        return type;
    }

    public TDataNodeLocation getTargetDataNode() {
        return targetDataNode;
    }

    public void setTargetDataNode(TDataNodeLocation targetDataNode) {
        this.targetDataNode = targetDataNode;
    }

    // Serialize interface for consensus log
    public abstract void serialize(DataOutputStream stream) throws IOException;

    // Deserialize interface for consensus log
    protected abstract void deserialize(ByteBuffer buffer) throws IOException;

    // Serialize interface for snapshot
    public abstract void serialize(OutputStream outputStream, TProtocol protocol)
            throws IOException, TException;

    // Deserialize interface for snapshot
    protected abstract void deserialize(InputStream inputStream, TProtocol protocol)
            throws TException, IOException;

    public static class Factory {

        public static RegionMaintainTask create(ByteBuffer buffer) throws IOException {
            int typeNum = buffer.getInt();
            if (typeNum >= RegionMaintainType.values().length) {
                throw new IOException("Unrecognized RegionMaintainType: " + typeNum);
            }
            RegionMaintainTask task;
            RegionMaintainType type = RegionMaintainType.values()[typeNum];
            switch (type) {
                case CREATE:
                    task = new RegionCreateTask();
                    break;
                case DELETE:
                    task = new RegionDeleteTask();
                    break;
                default:
                    throw new IOException("Unrecognized RegionMaintainType: " + typeNum);
            }
            task.deserialize(buffer);
            return task;
        }

        public static RegionMaintainTask create(InputStream inputStream, TProtocol protocol)
                throws IOException, TException {
            int typeNum = ReadWriteIOUtils.readInt(inputStream);
            if (typeNum >= RegionMaintainType.values().length) {
                throw new IOException("Unrecognized RegionMaintainType: " + typeNum);
            }
            RegionMaintainTask task;
            RegionMaintainType type = RegionMaintainType.values()[typeNum];
            switch (type) {
                case CREATE:
                    task = new RegionCreateTask();
                    break;
                case DELETE:
                    task = new RegionDeleteTask();
                    break;
                default:
                    throw new IOException("Unrecognized RegionMaintainType: " + typeNum);
            }
            task.deserialize(inputStream, protocol);
            return task;
        }

        private Factory() {
            // Empty constructor
        }
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (!(o instanceof RegionMaintainTask)) return false;
        RegionMaintainTask task = (RegionMaintainTask) o;
        return type == task.type && targetDataNode.equals(task.targetDataNode);
    }

    @Override
    public int hashCode() {
        return Objects.hash(type, targetDataNode);
    }
}
